Restoration of speech following total larynx removal is an integral part of the treatment plan for many patients with laryngeal cancer. This project is concerned with both fundamental and highly practical aspects of the speech restoration process. One broad objective of the proposed research is to expand current knowledge about acoustic characteristics of alaryngeal speech. Three specific aims of the initial phase of the project are (1) to complete detailed analyses of the acoustic properties of volume velocity functions of the voicing sources of esophageal and tracheoesophageal speakers, (2) to identify acoustic properties that differentiate voicing source outputs of normal, esophageal, and tracheoesophageal speakers, (3) to quantify neck tissue coupling and transmission properties underlying the use of neck-type artificial larynges. Specific aims of a second phase of the project are to complete detailed analyses of important articulatory-based acoustic properties of alaryngeal speech; namely, to delineate acoustic properties of vowels produced by tracheoesophageal speakers. In a third phase of this project, the aim is to develop a computer simulated LPC analysis-synthesis system for use initially by laryngectomized patients. The long-term goal of this phase of the project is to successfully incorporate new speech analysis and synthesis techniques into a variety of prosthetic devices or speech aids that alaryngeal and other types of communicatively impaired individuals can use to enhance oral communication.